Air heaters of steam-boiler furnaces



ct. 3D 1923.

J. REID AIR Hmvmfv oF STEAM BOILER FURNACES Filed April 19,

1921 2 Sheets-Sheet l J. REID AIR HEATER OF STEAM BOILER FURNAOES Oct. 30, 1923. 3,472,311@

Filed April l19. 1921 2 Sheets-Sheet 2 Patented @et 3U, i923..

nutren stares` JOHN nein, or'nonnon, ENGLAND.'

AIR HEATERS OF STEAM-BOILER FURNACES.

Application med April 19, 1921. sei-iai no. 462,675.

T 0 all whom t may concer/a.'

Be it known that l, JOHN REID, a subject of the King of Great Britain and Ireland, residing at London, England, have invented Improvements Relating to Air Heaters of Steam-Boiler Furnaces, of which the fol lowing is a specification.

This invention has reference to air heaters for forced draft urnaces,tl1e object being to facilitate repairs, inspection, cleaning or replacement, especially in the case of heaters of marine boiler furnaces.

By the adoption of a construction facilitatincr` the Vintroduction of standardized Withdrawable tube boxes, the said construction, moreover, being adapted to provide large air entrances and exits, and for the easy fiow of air at slow speed, and its smooth and even distribution to furnace fronts.

According to the present invention the air heater is built up of standardized sections eachl capable of bodily removal from the flue space in which it is located and the walls of said, space are formed with openings connnunicating'with air ducts located in such positions as to pick up available heat from the boiler, the arrangement being such that when the heater is in position the air from the fan Will pass to the heater, :follow the proper course therethrough and pass therefrom to ducts leading to the furnace front or qfronts.

Preferably separate standardized sections of the heater each comprise tube plates with connecting tubes through which the gases pass, and also, comprise side and end Walls. Fach section is mounted on suitable ledges or supports in the. smokebox oit the correv spending furnace above the level of the smoke tubes and' may be secured by bolts passing'through flanges on the outer ends ofi its side walls and tube plates and a cover plate. l phragms so as to give'air, admitted at the upper front side from a suitable air trunk connected to a tan, a zig-zag course through the section to lateral outlets at the bottom communicating with ducts arranged around and between the smoke boxes and leading the heated air to the furnaces. `Whcre outlets between adjacent sections face each other a depending partition may be arranged in the head ot the' common duct.

Referring to the accompanying drawings illustrating one embodiment of the invention, Fig. l is a sectional elevation in two Fach section is divided b v dia.

planes on the line (JL-O (Fig. 2) and with parts removed of an air'heater in three sections applied toa marine boiler having three furnaces;

Fig. 2 is a section on the line A A Fig. l; Fig. 3 is a section on the line B B Fig. l; Fig. e is a side view of one. section of the heater withdrawn and suspended by chains; Fig. 5 is a detail view showing to a larger scale and in section the connection of the air inlet duct to a heater section; and

Fig. 6 is a. detail' view illustrating the air heater supports and the air outlet ducts.

The three smoke boxes a a have at each side air ducts D, and, in the upper part of each smoke box above the level yof the smoke tubes al of the boiler, an air heater section is supported on angle irons c fixed to the smoke box walls which extend up to the top of the heater sections and form guides therefor and also serve to stitfen the back plate of the smoke bo-X against warping. Each heater section comprises upper and lower tube plates CZ connected by smoke tubes e, a back wall f, side walls g formed at the bott-om with air outlet apertures iz., and affront cover plate having at its upper part an air inlet aperture j; 7c is a dia# phragm to ensure the air taking a long course amongst the tubes and Z (Fig. 3) is an inclined partition to prevent the formation of eddies in the air current. The tube pla-tes (Z and side walls g are flanged at the front and the Yfront plate of the smoke boi; is formed with openings so that the section may be slid in and out on their bolts m (Fig. passing through the cover plate i, the .danges reterrcd 'to and the front plate of the smoke box securing each section when in position. Across the liront ot the upper parts. ot the heater "sections en tends au air supply duct a (Figs. 3 and il) which is secured to thecover plates by bolts o z ound the apertures j; flanged inouthpief... j) are Vattached 'to the duct, the flanges being adapted to extend into the openings y" to retard-leakage et air.y The air duct a communicateswith an air trunk not shown that extends to the back oi9 the boiler and is connected to a tan. al are Acurve battles to direct air into sections of the heater. f

The smoke box walls have apertures g' (F 1g. G) which coincide with the apertures 7i in the heaters and through which the heat ed al1 passes into the ducts e that rlead 1t supports c,

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y inlets and the hollow furnace .fronts indicated at ai Fig. 3; 7 a" are depending partitions between vopposed apertures g for smoothly diverting the air' down into the ducts b. v As will be understood in passing through the ducts b air is further heated since heat from the furnace gasesvin the smoke boxes Will be transmitted through the separating walls to the air.

What I claim is A 1. An air heater of a steam boiler comprising a removable heater section constructed as an interchangeable standardized unit, means for loosely supporting said section in the'uesp'aceof the boiler, means for detachably securing said section in position and ducts leading air to and from said section. i

2. An air heater of ,a steam boiler comprising a number of standardized/'heater sections each constructed as an interchangeable unit, means for independently supporting -eaoh such section in, the flue space of the boiler, means for independently and detachably securing each section in position, air

spective sections, an air supply duct cornmon to the several sections and connected to said inlets and ail,` ducts separatedby walls Vfrom the flue space and connected to the outlets of the sections.

3. A removable and interchangeable standardized box-like air heater section comprising upperand lower tube plates, tubes extending through said tube plates, a back Wall connecting the tube plates, side walls connecting said tube yplates and having air outlet apertures and a. front cover plate having an air inlet aperture, the Whole section being adapted to fit a'iue space which Iit is supported. A

' 4. A removable and standardized. interchangeable boX-like air heater .section c0mair outlets'pertain'ing to the reprising upper and lower tube platea-.tubes extending through said -tube plates, a back 4 5 it is supported and to be secured in place through vthe cover plates by bolts extending and said flanges.

5.^The combination with a marine'bo'iler of an air-heater which or each section of .which is standardized and capable of oodremoval from the flue space 'in which it 60 ily is locatedl whilst the walls of said space are formed With openings communicating with-air ducts located in such positions as toA pick up availableheat from theboiler,

the arrangement being such that when the heater is in position the air from the fan will ,pass to the heater, follow the proper course therethrough and pass therefrom to ducts leading to the furnace'front or fronts.

6. The combination with a marine boiler having at leastftWo furnaces of an fair heater in separate interchangeable standardized sections each comprising tube plates with connecting tubes through which `the Aor supports in the smokebox of the corresponding furnacefabove the level of the smoke tubes an air trunk connecting a fan with lan air-inlet at.v the front' of each section, lateral'outlets at the bottom of each 80 section and'communicating with ducts arranged around and between the smoke boxes and leading the heated air to the furnaces. Signed at London this 16th day of March,

. JOHN. REID.

plate adapted t'o extend 5o Gases pass and mounted on suitable ledges 

